Abstract:
Due to increase of population and rapid economic growth, percentage of heavy and recreational vehicles in the traffic stream from Colombo Capital to Central hills have increased causing severe traffic congestions. Specially all essential supplying services including fuel, food, export goods transport using major highways. Applying climbing lane concept on two-lane highways can be a good recommendation to reduce prevailing extreme conditions. “A climbing lane is, in effect, a passing lane added on an upgrade to allow traffic to pass heavy vehicles whose speeds are reduced”. However, application of Passing Climbing Lanes (PCL) are not a common practice in Sri Lanka. Most of steep upgrades on the major trans mountain highways do not have climbing lanes that cause traffic congestion on major highways. Due to the increasing vehicular traffic along the route, there exists an ongoing construction of Passing climbing lane on Colombo- Rathnapura-Wellawaya- Batticolo (CRWB) road near to Rathnapura. This study evaluates the Impact of Passing and Climbing lane on traffic flow on the particular section at CRWB road considering both travel time and delay time using the existing available data from RDA and new traffic survey data. The collected data at particular location before the construction of PCL and after is expected to show the importance of having PCLs at essential places along CRWB. Further, the impact of selected PCL has been analyzed for various traffic volume by a simulation model which was developed for this study. PCL is low cost improvement method rather than replacing extra lane or providing bypass lane, hence study discusses the economic advantages also.